2026 Aerodynamic & Chassis Regulations

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wuzak
wuzak
467
Joined: 30 Aug 2011, 03:26

Re: 2026 Aerodynamic & Chassis Regulations

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LionsHeart wrote:
07 Jun 2024, 12:33
Cs98 wrote:
07 Jun 2024, 09:41
What is actually included in that V6 weight? Is it just 30kg heavier to be cheaper to manufacture? Seems like an obvious place where you could've cut 15-20kg if that's the case. https://i.postimg.cc/XqG3gVd7/f126.jpg
Yes, it is very strange. It is as if they decided to use a thicker walled block and heavier pistons and connecting rods made of cast iron. It seems as if they wanted to use the same V6 architecture, so it is also unclear to me where the mass could have increased from? There is nothing to increase. I think there is a mistake in this picture.

151-4-7-25-100 = 15 free kilograms. From this we can assume that the current V6 turbocharged engines weigh around 115 kg.
From the 2026 rules:

5.7.1 The overall mass of the ICE must be a minimum of 130 kg.
5.5.4 The total mass of the turbocharger (TC) must be no less than 12kg.

The mass of the turbocharger is included in the minimum mass of the ICE. That is, the actual V6 mass is 118kg, or less, if the turbocharger is heavier.

5.1.2 Power unit (PU)
The internal combustion engine and turbocharger, complete with its ancillaries, the energy recovery system and all actuation systems and PU‐Control electronics necessary to make them function at all times.

5.7.2 The overall mass of the PU must be a minimum of 185 kg.
5.19.9 The minimum mass for the ES Main Enclosure PU Mass group elements as defined in Appendix 3 to these Regulations is 35.0kg. The procedure which will be used to determine this value may be found in the Appendix to the Technical and Sporting Regulations.
5.20.7 The total mass of the MGU‐K as defined in items 25 (MGU‐K) and 29 (ERS‐K phase conductors) of Appendix 3 to these regulations must be no less than 16.0kg.
5.20.8 The MGU‐K mechanical transmission including any shaft passing across the ICE/MGU‐K boundary will be assigned a mass of 4kg.


The PU mass includes the ICE mass, the MGUK mass and MGUK transmission mass and the Energy Store.

130kg + 16kg + 4kg +35kg = 185kg.


The current rules do not specify a minimum weight for the turbocharger.
5.5.1 The overall mass of the power unit must be a minimum of 151kg.
5.3.3 The mass of the MGU-K (as defined in line 12 of Appendix 3 to these regulations) may not be less than 7kg.
5.3.4 The mass of the MGU-H (as defined in line 14 of Appendix 3 to these regulations) may not be less than 4kg.
5.5.3 The total mass of the part of the ES that stores energy, i.e. the cells (including any clamping plates) and electrical connections between cells, must be no less than 20kg and must not exceed 25kg.

The ES is not included in the minimum mass for the PU.

Hadn't noticed this before:
5.13.6 The following elements of the power unit must be installed wholly within the survival cell:
a. ES elements as defined in lines 16 and 17 of Appendix 3 to these regulations.
b. Any DC-DC converter connected to ES HV DC bus. Includes active parts, enclosure, brackets and supports.
c. CU-K. Includes active parts, enclosure, brackets and supports.
d. CU-H. Includes active parts, enclosure, brackets and supports.
e. HV DC connections between ES and CU-K/CU-H/DC-DC converter. Includes all conductors, insulation, EMC screening, mechanical and thermal shielding.
The minimum values of volume and mass for these groups of components are 22.0 l and 31.0 kg respectively. The procedure which will be used to determine these values may be found in the Appendix to the Technical and Sporting Regulations.

Some, or all, of those items are included in the ES Main Enclosure mass.
151kg + 31kg = 182kg.

So the 2026 PUs are about 3kg heavier!

wuzak
wuzak
467
Joined: 30 Aug 2011, 03:26

Re: 2026 Aerodynamic & Chassis Regulations

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LionsHeart wrote:
07 Jun 2024, 14:52
Zynerji wrote:
07 Jun 2024, 14:33
LionsHeart wrote:
07 Jun 2024, 14:26


Why rev a turbo engine to 20,000 rpm? In the 1980s, 12,500 rpm was enough to produce over 1,200 horsepower in qualifying mode. Turbo engines usually do not have an extremely high rev because they are more efficient at low rpm due to excess air at the intake. The higher the rpm, the greater the mechanical and thermal losses. No power plant will be able to overcome 7 racing weekends if they spin at 20,000 rpm. And how high will the fuel consumption be? There will be no efficiency.
Ok. I'm talking best of both worlds. The RPM of the 2.4l V8 with the TJI and turbo of the 1.6l V6. Dropping the battery pack and expanding the fuel tank would help lots. Cheap engines means they can do 1 per race and wring them out. And you're correct. Turbo engines with all of the variables mentioned earlier can produce huge torque at low RPM. But that would then be part of the rubric that the teams must overcome, as horsepower overcomes drag, and it has a natural balance point. This is where a defined fuel restriction curve actually makes sense.

The reality of F1 is that most cars are actually good enough to win. It's finding the balance points on a collection of metric tensors that make "magical" races. If it was just easier for the teams to find this balance, the field would close up very quickly.
Ah, okay. I get it. You want to get rid of the battery and the motor generator altogether. In general, maybe that makes sense. But I doubt that it will improve the efficiency of the engine. I think we need to understand what exactly the goal of the FIA ​​and other structures is. What exactly they want. If the goal is to get the maximum possible engine power, then a hybrid is not needed. Please, the V12 or V10 of previous years have enough power. At Monza in the 2000s, they managed to get a speed of over 370 km / h. But if the goal is to get efficient engines, then there is no alternative to a hybrid.

I do not claim to know the truth, but I have some assumptions about what the internal combustion engine will be like in 2026.
So, most likely, the volume of the fuel tank will become smaller, which means that fuel consumption should become lower. By reducing the specific and instantaneous fuel consumption, it means that less air should enter the cylinders. I can only assume the following: the maximum rpm will be lower than now. Let's say 10,000-10,500 rpm. In this case, there is no need for a large turbocharger, which will have greater inertia. MGU-H is no longer there, which means there will be a large turbo lag. It can be reduced by reducing the size of the turbine. The rest should be compensated by MGU-K. How exactly the kinetic energy use map will be implemented, this is what the engine designers will have to decide. I think in general the system should be even more efficient and technologically simple. Perhaps this will even reduce the cost of power unit. And perhaps the resource of power unit will be even greater.
The efficiency of the ICE will not change if the ERS is ditched.

The overall efficiency might.

But, if we ditch the ERS you will lose 55kg + mass of cooling system for ERS and mass of cables, etc., not captured by the minimum mass rules.

It wouldn't be too far fetched for the loss to be 70-80kg, maybe even 100kg.

And then you also gain aero efficiency by requiring less cooling.

Would need to up the power of the ICE slightly, and would need an effective anti-lag system, which could be like the engine modes for the blown diffuser days, or could just add some extra fuel to keep the turbo spinning.

LionsHeart
LionsHeart
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Joined: 09 Mar 2023, 19:21

Re: 2026 Aerodynamic & Chassis Regulations

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wuzak wrote:
07 Jun 2024, 15:09
LionsHeart wrote:
07 Jun 2024, 12:33
Cs98 wrote:
07 Jun 2024, 09:41
What is actually included in that V6 weight? Is it just 30kg heavier to be cheaper to manufacture? Seems like an obvious place where you could've cut 15-20kg if that's the case. https://i.postimg.cc/XqG3gVd7/f126.jpg
Yes, it is very strange. It is as if they decided to use a thicker walled block and heavier pistons and connecting rods made of cast iron. It seems as if they wanted to use the same V6 architecture, so it is also unclear to me where the mass could have increased from? There is nothing to increase. I think there is a mistake in this picture.

151-4-7-25-100 = 15 free kilograms. From this we can assume that the current V6 turbocharged engines weigh around 115 kg.
From the 2026 rules:

5.7.1 The overall mass of the ICE must be a minimum of 130 kg.
5.5.4 The total mass of the turbocharger (TC) must be no less than 12kg.

The mass of the turbocharger is included in the minimum mass of the ICE. That is, the actual V6 mass is 118kg, or less, if the turbocharger is heavier.

5.1.2 Power unit (PU)
The internal combustion engine and turbocharger, complete with its ancillaries, the energy recovery system and all actuation systems and PU‐Control electronics necessary to make them function at all times.

5.7.2 The overall mass of the PU must be a minimum of 185 kg.
5.19.9 The minimum mass for the ES Main Enclosure PU Mass group elements as defined in Appendix 3 to these Regulations is 35.0kg. The procedure which will be used to determine this value may be found in the Appendix to the Technical and Sporting Regulations.
5.20.7 The total mass of the MGU‐K as defined in items 25 (MGU‐K) and 29 (ERS‐K phase conductors) of Appendix 3 to these regulations must be no less than 16.0kg.
5.20.8 The MGU‐K mechanical transmission including any shaft passing across the ICE/MGU‐K boundary will be assigned a mass of 4kg.


The PU mass includes the ICE mass, the MGUK mass and MGUK transmission mass and the Energy Store.

130kg + 16kg + 4kg +35kg = 185kg.


The current rules do not specify a minimum weight for the turbocharger.
5.5.1 The overall mass of the power unit must be a minimum of 151kg.
5.3.3 The mass of the MGU-K (as defined in line 12 of Appendix 3 to these regulations) may not be less than 7kg.
5.3.4 The mass of the MGU-H (as defined in line 14 of Appendix 3 to these regulations) may not be less than 4kg.
5.5.3 The total mass of the part of the ES that stores energy, i.e. the cells (including any clamping plates) and electrical connections between cells, must be no less than 20kg and must not exceed 25kg.

The ES is not included in the minimum mass for the PU.

Hadn't noticed this before:
5.13.6 The following elements of the power unit must be installed wholly within the survival cell:
a. ES elements as defined in lines 16 and 17 of Appendix 3 to these regulations.
b. Any DC-DC converter connected to ES HV DC bus. Includes active parts, enclosure, brackets and supports.
c. CU-K. Includes active parts, enclosure, brackets and supports.
d. CU-H. Includes active parts, enclosure, brackets and supports.
e. HV DC connections between ES and CU-K/CU-H/DC-DC converter. Includes all conductors, insulation, EMC screening, mechanical and thermal shielding.
The minimum values of volume and mass for these groups of components are 22.0 l and 31.0 kg respectively. The procedure which will be used to determine these values may be found in the Appendix to the Technical and Sporting Regulations.

Some, or all, of those items are included in the ES Main Enclosure mass.
151kg + 31kg = 182kg.

So the 2026 PUs are about 3kg heavier!
Thank you for the detailed answer! This is very interesting information. If this is true, then the main weight gain will be due to the smaller fuel tank, smaller chassis and wheel width?

LionsHeart
LionsHeart
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Joined: 09 Mar 2023, 19:21

Re: 2026 Aerodynamic & Chassis Regulations

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wuzak wrote:
07 Jun 2024, 15:17
LionsHeart wrote:
07 Jun 2024, 14:52
Zynerji wrote:
07 Jun 2024, 14:33


Ok. I'm talking best of both worlds. The RPM of the 2.4l V8 with the TJI and turbo of the 1.6l V6. Dropping the battery pack and expanding the fuel tank would help lots. Cheap engines means they can do 1 per race and wring them out. And you're correct. Turbo engines with all of the variables mentioned earlier can produce huge torque at low RPM. But that would then be part of the rubric that the teams must overcome, as horsepower overcomes drag, and it has a natural balance point. This is where a defined fuel restriction curve actually makes sense.

The reality of F1 is that most cars are actually good enough to win. It's finding the balance points on a collection of metric tensors that make "magical" races. If it was just easier for the teams to find this balance, the field would close up very quickly.
Ah, okay. I get it. You want to get rid of the battery and the motor generator altogether. In general, maybe that makes sense. But I doubt that it will improve the efficiency of the engine. I think we need to understand what exactly the goal of the FIA ​​and other structures is. What exactly they want. If the goal is to get the maximum possible engine power, then a hybrid is not needed. Please, the V12 or V10 of previous years have enough power. At Monza in the 2000s, they managed to get a speed of over 370 km / h. But if the goal is to get efficient engines, then there is no alternative to a hybrid.

I do not claim to know the truth, but I have some assumptions about what the internal combustion engine will be like in 2026.
So, most likely, the volume of the fuel tank will become smaller, which means that fuel consumption should become lower. By reducing the specific and instantaneous fuel consumption, it means that less air should enter the cylinders. I can only assume the following: the maximum rpm will be lower than now. Let's say 10,000-10,500 rpm. In this case, there is no need for a large turbocharger, which will have greater inertia. MGU-H is no longer there, which means there will be a large turbo lag. It can be reduced by reducing the size of the turbine. The rest should be compensated by MGU-K. How exactly the kinetic energy use map will be implemented, this is what the engine designers will have to decide. I think in general the system should be even more efficient and technologically simple. Perhaps this will even reduce the cost of power unit. And perhaps the resource of power unit will be even greater.
The efficiency of the ICE will not change if the ERS is ditched.

The overall efficiency might.

But, if we ditch the ERS you will lose 55kg + mass of cooling system for ERS and mass of cables, etc., not captured by the minimum mass rules.

It wouldn't be too far fetched for the loss to be 70-80kg, maybe even 100kg.

And then you also gain aero efficiency by requiring less cooling.

Would need to up the power of the ICE slightly, and would need an effective anti-lag system, which could be like the engine modes for the blown diffuser days, or could just add some extra fuel to keep the turbo spinning.
Well, I mean overall efficiency as the mass of fuel spent over the full race distance. It all depends on what goal the rules regulator is pursuing. Previously, before the hybrid era, 150 kg of fuel was allowed per race without refueling? Then, since 2014, only 100 kg. Then they increased the chassis size and required 110 kg. I think their main goal is some kind of limit of less than 90 kg per race. Well, this is just an assumption.

Cs98
Cs98
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Joined: 01 Jul 2022, 11:37

Re: 2026 Aerodynamic & Chassis Regulations

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Vanja #66 wrote:
07 Jun 2024, 15:02
yooogurt wrote:
07 Jun 2024, 14:53
A team member who spoke to formu1a.uno , said that it is indeed possible to reach 400 km/h, but due to limitations in terms of electricity use it will be difficult.
People are not aware of the magnitude of cutting down 55% of drag, for the same power of around 1000HP you get a car reaching 300kmh jump to 390-400kmh. Anything over 330-340kmh in typical races is too much kinetic energy for a worst-case crash, so this will of course mean a lot less energy used during a race. Active aero allows unbelievable efficiency figures and I think in 27 or 28 teams and FIA will agree to increase the wings a bit, maybe even in the final 2026 rule set
55%, I'm skeptical about that figure, these are still open wheel cars where the tyres are a huge drag factor. Maybe best case scenario when you compare the FIA model in "mode X" with a current spec car in Monaco trim with DRS closed you can approach that 50%. But that's before the teams sink their teeth in and try to regain some of that lost downforce. The FIA is usually very optimistic with their numbers, it was the same in 2022.

Also thinking about what Dr Obbs was hearing behind the scenes, basically that the wings are drag neutral in "mode X", which means if the mechanism fails they will stay open and cause a crash. They'll probably have to change that to something like current DRS where it still induces a bit of drag so that it closes in case of failure.

TeamKoolGreen
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Joined: 22 Feb 2024, 01:49

Re: 2026 Aerodynamic & Chassis Regulations

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Cs98 wrote:
07 Jun 2024, 09:41
What is actually included in that V6 weight? Is it just 30kg heavier to be cheaper to manufacture? Seems like an obvious place where you could've cut 15-20kg if that's the case. https://i.postimg.cc/XqG3gVd7/f126.jpg
The MGU-K and battery are bigger and heavier in the 2026 car. The MGU-H is gone but it only weighed 4 kg. Which is ironic because the MGU-H was one of the most weight efficient things on the car.

They should have made the MGU-H a spec part to control the cost instead of eliminating it.

TeamKoolGreen
TeamKoolGreen
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Joined: 22 Feb 2024, 01:49

Re: 2026 Aerodynamic & Chassis Regulations

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yooogurt wrote:
07 Jun 2024, 14:53
A team member who spoke to formu1a.uno , said that it is indeed possible to reach 400 km/h, but due to limitations in terms of electricity use it will be difficult.
Christian Horner and Red Bull sounded the alarm about this over a year ago. And nobody wanted to listen. Thankfully this is being so badly handled that we will probably squeeze at least another year out of the current formula.

wuzak
wuzak
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Re: 2026 Aerodynamic & Chassis Regulations

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TeamKoolGreen wrote:
07 Jun 2024, 18:25
Cs98 wrote:
07 Jun 2024, 09:41
What is actually included in that V6 weight? Is it just 30kg heavier to be cheaper to manufacture? Seems like an obvious place where you could've cut 15-20kg if that's the case. https://i.postimg.cc/XqG3gVd7/f126.jpg
The MGU-K and battery are bigger and heavier in the 2026 car. The MGU-H is gone but it only weighed 4 kg. Which is ironic because the MGU-H was one of the most weight efficient things on the car.

They should have made the MGU-H a spec part to control the cost instead of eliminating it.
The battery is nominally the same size - 4MJ.

The actual capacity is larger.

The weight of the ES won't be much different, if at all.

The headline weight of 35kg for 2026 and 20-25kg for the current rules are not directly comparable, as the 2026 ES includes items not included in the current rules.

wuzak
wuzak
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Re: 2026 Aerodynamic & Chassis Regulations

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Formula E has a battery of 284kg and capacity of 51kWh = 183.6MJ.

Using 25kg for the Formual 1 battery would suggest the actual capacity is 16MJ.

Using the allowable battery capacity for Formula E of 38.5kWh = 138.6MJ, teh Formula 1 battery woudl have a capacity of 12MJ.

mzso
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Re: 2026 Aerodynamic & Chassis Regulations

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Zynerji wrote:
07 Jun 2024, 14:33
LionsHeart wrote:
07 Jun 2024, 14:26
Zynerji wrote:
07 Jun 2024, 14:08
Meh.

Cars are cool-ish, but why ruin it with the hybrid nonsense?

They could have just 1.6l V6 turbo and pushed them to 20k RPM, and would have had a much lighter, cheaper, uncomplicated machine that had more fan appeal.

Removing the VLIM system and such is just nonsense at this point. If they want to go for efficiency, VLIM/VLEM , VVT, VDT, TJI and the rest are all efficiency controllers. Those variables are imperative to getting the most power/RPM. For downsizing at the auto industry level, one would think that developing a tightly packaged power unit that can be tuned to meet any specific vehicle demand would just be a Unicorn that they would chase.
Why rev a turbo engine to 20,000 rpm? In the 1980s, 12,500 rpm was enough to produce over 1,200 horsepower in qualifying mode. Turbo engines usually do not have an extremely high rev because they are more efficient at low rpm due to excess air at the intake. The higher the rpm, the greater the mechanical and thermal losses. No power plant will be able to overcome 7 racing weekends if they spin at 20,000 rpm. And how high will the fuel consumption be? There will be no efficiency.
Ok. I'm talking best of both worlds. The RPM of the 2.4l V8 with the TJI and turbo of the 1.6l V6. Dropping the battery pack and expanding the fuel tank would help lots. Cheap engines means they can do 1 per race and wring them out. And you're correct. Turbo engines with all of the variables mentioned earlier can produce huge torque at low RPM. But that would then be part of the rubric that the teams must overcome, as horsepower overcomes drag, and it has a natural balance point. This is where a defined fuel restriction curve and a 1000hp cap actually makes sense.

The reality of F1 is that most cars are actually good enough to win. It's finding the balance points on a collection of metric tensors that make "magical" races. If it was just easier for the teams to find this balance, the field would close up very quickly.
20k rpm is not the best, nor is it good in any way. For more power hybrid or not, they need to increase fuel flow. High rpm is just an artifact of having other means of increasing speed restricted. It sucks for both durabilty, and efficiency.

wuzak
wuzak
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Joined: 30 Aug 2011, 03:26

Re: 2026 Aerodynamic & Chassis Regulations

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mzso wrote:
07 Jun 2024, 19:29
Zynerji wrote:
07 Jun 2024, 14:33
LionsHeart wrote:
07 Jun 2024, 14:26


Why rev a turbo engine to 20,000 rpm? In the 1980s, 12,500 rpm was enough to produce over 1,200 horsepower in qualifying mode. Turbo engines usually do not have an extremely high rev because they are more efficient at low rpm due to excess air at the intake. The higher the rpm, the greater the mechanical and thermal losses. No power plant will be able to overcome 7 racing weekends if they spin at 20,000 rpm. And how high will the fuel consumption be? There will be no efficiency.
Ok. I'm talking best of both worlds. The RPM of the 2.4l V8 with the TJI and turbo of the 1.6l V6. Dropping the battery pack and expanding the fuel tank would help lots. Cheap engines means they can do 1 per race and wring them out. And you're correct. Turbo engines with all of the variables mentioned earlier can produce huge torque at low RPM. But that would then be part of the rubric that the teams must overcome, as horsepower overcomes drag, and it has a natural balance point. This is where a defined fuel restriction curve and a 1000hp cap actually makes sense.

The reality of F1 is that most cars are actually good enough to win. It's finding the balance points on a collection of metric tensors that make "magical" races. If it was just easier for the teams to find this balance, the field would close up very quickly.
20k rpm is not the best, nor is it good in any way. For more power hybrid or not, they need to increase fuel flow. High rpm is just an artifact of having other means of increasing speed restricted. It sucks for both durabilty, and efficiency.
Of having capacity limits and no boost?

Doubtful the current PUs woudl rev past 10k if the maximum fuel flow was the same regardless of rpm, rather than the ramp used in the current (and 2026) rules.

Luscion
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Re: 2026 Aerodynamic & Chassis Regulations

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https://www.motorsport.com/f1/news/f1-t ... /10620643/
Currently central to the concern is the fact that some teams feel the FIA has pushed on with elements of the rules which they do not think will work in the way they are intended.

This includes the overall aerodynamic concept, with some teams suggesting that the new cars could be especially slow because they will be lacking downforce and frequently run out of battery power.
There are fears that teams will find it impossible to get anywhere near close to that and will end up spending an enormous amount of money in trying to find marginal gains.

Teams also want more details about the state of the active aero plans, with the FIA having said it intends to introduce a dual state system – with wings in a Z-mode for high downforce and a low-drag X-mode for the straights.

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organic
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Re: 2026 Aerodynamic & Chassis Regulations

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Could be what Dr obbs was referring to with teams unhappy


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JordanMugen
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Re: 2026 Aerodynamic & Chassis Regulations

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mzso wrote:
07 Jun 2024, 12:42
They should define a maximum length
There is! 3400mm plus the specified overhangs.

You suppose that should be 3000mm or less?

Interestingly F2 car length is 5220mm with wheelbase 3135mm.

mzso wrote:
07 Jun 2024, 13:03
I think no-one ine the world uses such such high profile tires for road racing, outside F1.
Even F1 didn't use 13-inch rims in the 1960's! Most late 1960's F1 cars used 15-inch rims the same as USAC/Indy racing.

USAC/Indycar stuck with 15-inch to the present day, where FISA/FIA mandated 13-inch rears in ~1972 and 13-inch fronts in ~1983.

Is it a generalisation to say that taller tyres (or tyres with softer sidewalls, extreme case being drag racing tyres) have more longitudinal grip on dry tarmac and shorter tyres (or tyres with stiffer sidewalls) have more lateral grip on dry tarmac (i.e., potentially a better lap time even despite greater rotational mass of a bigger wheel and shorter tyre)? Or does that road car thinking not apply to Grand Prix cars? :?:

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JordanMugen
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Re: 2026 Aerodynamic & Chassis Regulations

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Cs98 wrote:
07 Jun 2024, 15:28
55%, I'm skeptical about that figure, these are still open wheel cars where the tyres are a huge drag factor.
I wonder why the FIA ruled out the use of a partial rear wheel fairing, similar to on the current Indycar spec aerokit? :?:

[Or the original Dallara DW12 or Formula E type triangular bodywork, but I like the current Indycar style with elements of a both a sidepod and fairing. :) ]

Would such fairings create outwash ahead of the rear wheels, which is undesired in the 2026 regulation set? :?: